architecture blog

Cool roofs are not tricky. They are what they claim to be: roofs
that are cool in temperature. So although the concept is simple, the
result is a very powerful tool for architects in the growing need and
desire for greener buildings.

1. The Basics

In essence, the goal of a cool roof is to reduce the amount of heat entering the building. As
seen in the diagram below, these two properties, solar reflectance and
thermal emittance are what determine if a roof is technically cool.

The
beauty of cool roofs is that they're a low-tech concept. Long before
the days of electricity and air conditioning, warm-climate areas used
light colors in their buildings to reduce heat gain. I think I even
wrote something about this last year called Environmental Architecture in Greece.

In Santorini, Greece, cool roofs (and walls) are not a new idea.

However, since people don't always want white roofs, some smart
scientist types have figured out a way to have cool roofs with
darker colors by utilizing special highly reflective
coatings. Cool roofs are versatile, coming in all types of materials that can be applied to a home just as easily as to an office or industrial building.

3. Cost

Inevitably, the first question we get after we describe a green
feature to a client is "That's great, but is it more expensive?" Thankfully, for
cool roofs, the answer is "not really." The added cost for a cool roof
can be as little as 15 percent. This minor increase is far outweighed by
the projected 20 percent or more savings in air conditioning cost (source). Besides, knowing you have a cool roof and are helping the environment will make you feel warm and fuzzy
inside.

Compared to other green building features with high upfront costs, such as solar panels, cool roofs are an affordable option.

4. It's Not Just About You

Don't be selfish when selecting a new roof. Having
a hot roof not only increases your cooling costs, it also affects the world around you through an ugly phenomenon called heat island effect.

Heat
island effect occurs as result of the numerous heat-absorbing surfaces
that cities contain such as dark colored roofs, streets and seas of
parking lots. This effect overheats urban areas, increasing the demand for air conditioning and electricity. Another not-so-fun aspect of heat island effect is that it's known to increase smog
formation.

5. For Remodels Too

Whereas many green building features are better suited for new construction or extensive remodels, cool roofs are a viable option for any remodel or simple re-roofing.

On our recent remodel of the Fashion Square Car Wash, we specified a cool roof to reduce the air conditioning loads and heat island effect from the surrounding paved areas.

The re-roofing of the Fashion Square Car Wash started out looking very similar to a typical roof. So far, not very cool.

That's a little better.

Now there's a cool roof.

So in this case, the roofing was pretty standard, but in the end it was covered with a white coating to increase its reflectivity.

6. Location, Location Location

There is a fair amount of debate
as to whether cool roofs are beneficial in all climate zones. For us here in
Los Angeles and other warm climates (hey Texas, Nevada and Arizona), it's a
no-brainer:
cool roofs work. The worry in cooler climates is that cool
roofs don't allow for thermal gain in the winter. The good news is that
there are numerous studies that have shown that cool roofs are effective in just about any climate.

Potential net energy savings from changing roof reflectivity. Savings are measured in dollars. Note that the net savings are the savings of cooling energy use less the penalties of heating energy use. Image courtesy of the Heat Island Group.

If you have any thoughts on cool roofs, feel free to leave a comment or send us a fancy form message.

One of the major components the energy efficiency of any building is insulation. Insulation is critical to maintaining comfortable indoor temperatures by either keeping the heat in or out of a building.

Green Insulation

As sustainability gains momentum in the building industry, new products are available that rethink insulation. One of these is recycled denim insulation. Yes, old jeans. One of the leading manufactures of this green product is UltraTouch.

Don't Eat the Pink Stuff

UltraTouch Natural Cotton Fiber Insulation is targeted as a replacement for traditional fiberglass insulation - the typically yellow or pink soft looking stuff you see between the studs during construction. Yes, you're probably also picturing the pink panther. If you haven't had the pleasure of handling traditional fiberglass insulation, don't. It's not pleasant stuff to to touch (itchy) or breath (can cause respiratory problems). I definitely wouldn't wear pants made of the stuff. UltraTouch on the other hand is made of safe, easy to handle, recycled denim.

UltraTouch comes in rolls and is easily installed.

Product Info

So aside from this obvious point that it the product is safer for people to install, here are a few other interesting factoids:

The insulation is 85% post industrial recycled fibers.

Has acoustic ratings approximately 30% better than traditional insulation. Less outside or neighborly noise.

Cost

A common question, as with most green products, is does it cost more? Well, yes, it does. How much more depends on the size of your project and the construction market. However, the short and long term benefits of this product far outweigh the upfront costs.

At Modative, we are now specifying this or similar products instead of traditional fiberglass insulation. If you are concerned about the cost, we're happy to help you compare the cost of this green product to traditional insulation.